Method for setting user equipment identifier in radio communication system

ABSTRACT

The present invention is directed to a method for setting a user equipment identifier as user equipment identification information used when data received through a dedicated logical channel is transmitted through a common transport channel. The method includes transmitting data and a message type indicator as user equipment identification information from a RRC layer to an RLC layer; setting a user equipment identifier indicator according to the received message type indicator in the RLC layer and transmitting it with the data to a MAC layer; and selecting a user equipment identifier type and a user equipment identifier according to the set user equipment indication identifier, adding it to a header of a MAC SDU in the MAC layer and transmitting it to a corresponding MAC layer in a receiving device.

CROSS REFERENCE TO RELATED ART

[0001] This application claims the benefit of Korean Patent ApplicationNo. 2001-40710, filed on Jul. 7, 2001, which is hereby incorporated byreference in its entirety.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a method for setting aterminal(user equipment) identifier in a mobile communication system asterminal (user equipment) identification information, when datadelivered through a dedicated logical channel is transmitted through acommon transport channel. More specifically, it relates to a method forsetting a user equipment identifier in a UMTS (Universal MobileTelecommunications System, European type IMT-2000 radio communicationsystem). As data (RLC SDU; Radio Link Control Service Data Unit) andmessage type indicator, which serve the purpose of user equipmentidentification information, are transmitted from a RRC (Radio ResourcesControl) layer to an RLC (Radio Link Control) layer, the RLC layer setsa user equipment identifier indicator according to the transmittedmessage type indicator and transmits it with the data to a MAC (MediumAccess Control) layer. In turn, the MAC layer adds the appropriate userequipment identification information to the data received.

[0004] 2. Description of the Related Art

[0005] For the purpose of making specifications for third generationmobile communication systems(IMT-2000 systems) based on evolved GSM corenetwork and W-CDMA radio access network and specifications for userequipment for the system, a group of standard developingorganizations(SDOs) including ETSI of Europe, ARIB/TTC of Japan, T1 ofU.S. and TTA of Korea established a unified SDO in the name of ThirdGeneration Partnership Project (“3GPP”). 3GPP is developing thirdgeneration mobile communication systems (IMT-2000 system) providing highperformance multimedia services including audio, video and data over aradio network.

[0006] For the purpose of efficient management and technologicaldevelopment, five Technical Specification Groups (“TSGs”) are organizedunder 3GPP. Each TSG is in charge of approving, developing and managingspecifications related to a pertinent field. Among them, RAN (RadioAccess Network) group has developed functions, requirements andinterface specifications related to user equipment and UMTS (UniversalMobile Telecommunications System, European type IMT-2000 System)Terrestrial Radio Access Network (“UTRAN”) in order to set a new radioaccess network specification to the third generation mobilecommunication system.

[0007] A TSG-RAN group consists of one plenary group and four workinggroups. WG1 (working group 1) has been developing specifications for aphysical layer (first layer), and WG2 has been specifying functions of adata link layer (second layer) and a network layer (third layer). Inaddition, WG3 has been developing specifications for interfaces amongbase stations, RNCs (Radio Network Controller) and core networks in theUTRAN. Lastly, WG4 has been discussing requirements for radio linkperformance and radio resource management.

[0008]FIG. 1 illustrates a structure of the UTRAN.

[0009] As depicted in FIG. 1, the UTRAN 20 includes a Node B and an RNC.Node B is controlled by the RNC, and works as an access point byreceiving uplink information from the user equipment 10 and bytransmitting downlink information from the UTRAN through the physicallayer linking. The RNC performs allocation and management of radioresources.

[0010] The RNC can be classified as either control or serving RNC.First, the control RNC directly manages Node B and manages common radioresources. Next, the serving RNC manages dedicated radio resourcesallocated to each user equipment.

[0011] The control RNC and the serving RNC can be the same. However,when a user equipment moves from a serving RNC's region to other RNC'sregions, a control RNC and a serving RNC can be different.

[0012] Accordingly, when the control RNC and the serving RNC aredifferent, data to be transmitted to a user equipment is transmitted toa control RNC after passing through a serving RNC and transmitted to auser equipment through a Node B connected to the control RNC.

[0013] As depicted in FIG. 1, a Radio Network Sub-system (“RNS”)includes one RNC and several Node Bs. In addition, the RNS where aserving RNC is located is referred to as serving RNS.

[0014]FIG. 2 illustrates a structure of a general radio interfaceprotocol according to a radio access network specification of the 3GPP.

[0015] A radio interface protocol between a user equipment and the UTRANis horizontally divided into a physical layer (first layer), a data linklayer (second layer) and a network layer (third layer). It is alsovertically divided into a control plane for control signaling and a userplane for data information transfer.

[0016] As to the vertical division, first, the control plane contains aradio resource control (“RRC”) layer, a radio link control (“RLC”)layer, a medium access control (“MAC”) layer and a physical layer as thefirst layer. Next, the user plane contains a packet data convergenceprotocol (“PDCP”) layer, a broadcast/multicast control (“BMC”) layer, anRLC layer, a MAC layer and a physical layer.

[0017] The physical layer provides information transfer service to anupper layer by using various radio transfer techniques. It is connectedto the MAC layer as an upper layer through transport channels. The databetween the MAC layer and the physical layer are transmitted through thetransport channels. The transport channels are classified as a DTCH(Dedicated Transport Channel) and a CTCH (Common Transport Channel). TheDTCH is a transport channel exclusively used by one user equipment, andthe CTCH is a transport channel jointly used by several user equipment.

[0018] The MAC layer provides a reallocation service of a MAC parameterfor allocating and reallocating radio resources. It is connected to theRLC layer through a logical channel, and various logical channels areprovided according to the type of information transmitted. In general, acontrol channel is used when transmitting information on the controlplane, and a traffic channel is used when transmitting information onthe user plane.

[0019] The RLC layer provides the function of setting and releasingradio links. In addition, it performs segmenting and reassemblingfunctions of an RLC Service Data Unit (“SDU”) delivered from an upperlayer on the user plane. The size of the RLC SDU is adjusted on the RLClayer to be suitable for a processing capacity. Afterwards, headerinformation is added, and it is transmitted to the MAC layer as an RLCProtocol Data Unit (“PDU”) format.

[0020] Since the PDCP layer is an upper layer of the RLC layer, itconverts the data of packet network protocols, such as IPv4 or IPv6,into the data of a format suitable for the RLC layer, and vice versa. Inaddition, it assists the lower layers to transfer data through the radiointerface efficiently by reducing unnecessary control information usedin a wire network. That function is referred to as header compression,and, for example, the header compression can be used to reduce TCP/IPheader information.

[0021] The BMC layer exists on the user plane, and it is used forapplying a broadcast service or a multicast service to the system havinga radio interface.

[0022] The RRC provides information broadcast services to all userequipment located within a certain area. In addition, it performs acontrol plane signal processing for a control signal exchanging betweenthe third layers of transmitting and receiving side and has functionsfor setting/maintaining/releasing radio resources between user equipmentand the UTRAN. In particular, the RRC has functions forsetting/maintaining/releasing a Radio Bearer andallocating/reconfiguring/releasing radio resources required for radioaccess networking. Herein, the Radio Bearer means a service provided bythe second layer for data transfer between the user equipment and theUTRAN. That is, setting a radio bearer means specifying thecharacteristics of a protocol layer and a channel required to provide acertain services, and setting specific parameters and operation method.

[0023] Each user equipment also includes all radio interface layers.However, in the UTRAN, protocol layers are dispersed in severalconstituent elements of a UTRAN (UMTS Terrestrial Radio Access Network).

[0024]FIG. 3 illustrates an example of a protocol layer hierarchycorresponding to the constituent elements of a Radio Access Network. Ingeneral, the RLC layer is placed in the serving RNC. The functions ofthe MAC layer can be divided according to the type of a transportchannel and can be placed either in the serving RNC or in the controlRNC.

[0025] As depicted in FIG. 3, when two RNCs are operated concurrently asa serving RNC and a control RNC, the MAC layer is divided into a MAC-dsub layer and a MAC-c/sh sub layer according to the type of transportchannel. These are respectively placed in the serving RNC and thecontrol RNC.

[0026] In comparison, when one RNC is operated commonly as the servingRNC and the control RNC, a MAC-c/sh sub layer and a MAC-d sub layer areplaced on the same RNC. This is because the MAC-d sub layer manages adedicated logical channel, which is dedicated to a user equipment, andthe MAC-c/sh sub layer manages a common transport channel. Because theMAC-s/sh sub layer manages the common transport channel, which isjointly used by all user equipment within the cell, each cell has oneMAC-c/sh layer. Because the MAC-d sub layer provides a dedicated serviceto a user equipment, and one MAC-d sub layer exists for each one userequipment. The physical layer (PHY) is placed in the Node B.

[0027]FIG. 4 illustrates a structure of an RLC layer and a MAC layer inthe UTRAN. In a down_link, when data is delivered to the RLC layer froman upper layer, the RLC layer stores an RLC PDU in an RLC buffer andtransmits a certain number of PDUs corresponding to a request from theMAC layer.

[0028] The RLC PDU received in the MAC-d layer is transmitted throughDedicated Transport Channel (DTCH) or Common Transport Channel (CTCH) bychannel switching. When it is transmitted through DTCH, a related headeris added to it in the MAC-d sub layer, and it is transmitted to thephysical layer through a Dedicated Channel (DCH).

[0029] However, the RLC PDU is transmitted through the CTCH, it istransmitted from the MACd sub layer to the MAC-c/sh sub layer, and arelated header is added on. Thereafter, it is multiplexed through otherlogical channels and is transmitted through the common transport channelsuch as PCH (Paging Channel), FACH (Forward Access Channel) and DSCH(Downlink Shared Channel) etc.

[0030] In an up_link, data is received through the Dedicated Channel(DCH) and the common transport channel (CTCH) such as RACH (ReverseAccess Channel) and CPCH (Common Packet Channel) etc., and the data issubsequently transmitted to an upper layer.

[0031] In that case, the data is transmitted to the RLC layer via thepath converse in the down_link. The structures of the RLC layer and theMAC layer in the user equipment are almost the same as the structure inFIG. 4.

[0032] To illustrate, the transmission of data through FACH (ForwardAccess Channel) as the common transport channel will be described withreference to FIG. 4.

[0033] Because the RLC PDU transmitted from the RLC layer uses the FACHof the MAC-c/sh sub layer, it is transmitted to the MAC-c/sh sub layerthrough channel switching and control transmission multiplexing. Thecontrol transmission multiplexing means multiplexing several logicalchannels.

[0034] Data transmitted to the MAC-c/sh sub layer is multiplexed withdata of other logical channels. In addition, because the data of varioususer equipment can be transmitted through the common transport channel,to identify a user equipment to receive pertinent data, a destinationuser equipment's identifier is added to the MAC PDU through a userequipment identifier inserting for data multiplexing. Herein, a TCTF(Target Channel Type Field) mapping for data multiplexing maps therelationship between the logical channel and the transport channel. Datamapped by the FACH transport channel is transmitted to the FACH based ona data transmission schedule by considering the priority of the userequipment.

[0035] The RLC PDU delivered from the RLC layer of the UTRAN or the userequipment to the MAC layer through the logical channel is transmitted tothe physical layer through an appropriate transport channel.

[0036] Herein, when the data passed the dedicated logical channel istransmitted through the common transport channel as described above, itpasses through the MAC-d sub layer and the Mac-c/sh sub layer andultimately transmitted to the physical layer.

[0037] In that case; MAC PDU header information, which is added by eachpart of the MAC layer, can include a TCTF field, a user equipmentidentifier type field, a user equipment identifier field and a C/T fieldetc.

[0038] The TCTF field indicates the following: the type of a logicalchannel the data of which is transmitted through a specific transportchannel; the user equipment identifier type field indicating which userequipment identifier among various types of user equipment identifiersis used; the user equipment identifier field including identificationinformation of a user equipment designated in the user equipmentidentifier type field; and the C/T field which provides information fordistinguishing each logical channel when data of several logicalchannels are transmitted to one transport channel.

[0039] A user equipment identifier, used for identifying a userequipment on the MAC-c/sh sub layer shown in FIG. 4, can be divided intotwo types according to a user equipment's distinguishable geographicalregion (i.e. a range in which each user equipment can cover) in anetwork.

[0040] First, a C-RNTI (Cell Radio Network Temporary Identity) isallocated by the control RNC when a user equipment is linked to a newcell. Accordingly, the C-RNTI has unique value only in a pertinent cell,and a cell region is the effective region of the C-RNTI. Therefore, whenthe user equipment moves to another cell, the C-RNTI has to be changed.

[0041] Second, a U-RNTI (UTRAN Radio Network Temporary Identify) is usedfor identifying a certain user equipment in the UTRAN, and it iscomposed of a S-RNTI (SRNC RNTI) and a serving RNC identifier. TheS-RNTI is an identification value used for identifying a certain userequipment in the serving RNC, and each user equipment has a uniqueS-RNTI value in the serving RNC. In addition, the serving RNC identifieris used to identify the RNC in the UTRAN. Accordingly, in order todesignate a certain user equipment in the UTRAN, serving RNC identifierinformation and an identification value of the user equipment in thepertinent RNC are required.

[0042] Accordingly, the U-RNTI is a unique value in the UTRAN and is notchanged even in cases where the use equipment is moved to a differentcell in a RNS. However, when the serving RNC identifier is changed dueto the change of the serving RNC, a new U-RNTI value has to beallocated. More specifically, a U-RNTI effective range is a regionmanaged by a serving RNC.

[0043] In a system compliant with the 3GPP standard, a user equipment isidentified by using only one of the two types of user equipmentidentifier: with the C-RNTI, a 16 bit is required, and with the U-RNTI,a 32 bit is required. Accordingly, by using C-RNTI the limited radiochannel resources can be efficiently used. In some cases, a value of theU-RNTI is used. For example, when a C-RNTI value is changed frequently,a user equipment can be identified effectively by using a U-RNTI value.

[0044] However, in the conventional system compliant with the 3GPPstandard, identification information of a user equipment is added to aMAC PDU by the MAC layer of the transmitter side, and the identificationinformation of the user equipment is identified in the receiver side ofthe MAC layer. Though, the transmitter side MAC layer performsmultiplexing of an RLC PDU transmitted from the RLC layer and addingidentification information of a user equipment to a MAC PDU(a data unitcorresponding to the RLC PDU), the MAC layer is unable to recognize whenand which type of user equipment identifier is used, and can not changethe type of user equipment identifier dynamically.

SUMMARY OF THE INVENTION

[0045] In order to facilitate in determining when and which type of auser equipment identifier must be used in a MAC layer, a method fordetermining information required for setting a user equipment identifier(C-RNT, U-RNTI) from other layers to a MAC (Medium Access Control) layerand a method for setting a user equipment identifier value are explainedbelow.

[0046] Additional features and advantages of the invention will be setforth in the description which follows, and in part will be apparentfrom the description, or may be learned by practice of the invention.The objectives and other advantages of the invention will be realizedand attained by the structure particularly pointed out in the writtendescription and claims hereof as well as the appended drawings.

[0047] To further illustrate, when data received through a dedicatedlogical channel is transmitted through a common transport channel, it isnecessary to distinguish a user equipment which is the destination ofthe data by using a user equipment identifier in the MAC layer. Thus, amethod for setting a user equipment identifier, which is to be added toa MAC PDU header, is provided below.

[0048] The steps in setting a user equipment identifier with the presentinvention are as follows: 1) transmitting data and a message typeindicator as user equipment identification information from a RRC (RadioResources Control) layer to an RLC (Radio Link Control) layer; 2)setting a user equipment identifier indicator according to the receivedmessage type indicator in the RLC layer and transmitting it with thedata to a MAC (Medium Access Control) layer; 3) selecting a userequipment identifier type and a user equipment identifier according tothe set user equipment indication identifier, adding it to a header of aMAC PDU (Medium Access Control Protocol Data Unit) in the MAC layer; and4) transmitting it to a reception side MAC layer. (A MAC PDU is composedof a header and a MAC SDU. MAC SDU is substantially the same as RLCPDU.) The method further includes: performing a radio transmission inthe MAC layer as a MAC PDU (Medium Access Control Protocol Data Unit)format; adding a user equipment identifier type field indicating a userequipment identifier field and the type of a user equipment identifierto the MAC PDU header; and transmitting it to the reception side anddistinguishing a user equipment by using the MAC PDU header informationin the reception side.

[0049] The RLC layer receives data (RLC SDU) and a message typeindicator as user equipment identification information from the RRClayer and sets a user equipment identifier indicator for distinguishinga user equipment appropriate to a network region managing the userequipment in a mobile communication system. The MAC layer receives theuser equipment identifier indicator designating the type (U-RNTI,C-RNTI) of user equipment identifier, and the MAC layer sets userequipment identifier and a user equipment identifier type field as MACPDU header information.

[0050] The type of a user equipment identifier is determined whensetting the radio bearer, and the set user equipment identifierindicator is transmitted from the RLC layer to the MAC layer in atransmission session using the set radio bearer.

[0051] The user equipment identifier indicator is updated by controlinformation on the RRC layer when the type of user equipment identifieris changed.

[0052] The type of user equipment identifier is set according to thetype of data (RLC SDU) transmitted from the RRC layer to the RLC layer.

[0053] According to an embodiment of the present invention, a method forsetting a user equipment identifier in a radio communication systemhaving a plurality of protocol layers comprises: providing data and aparameter associated with a user equipment identifier type indicatorfrom a third protocol layer to a second protocol layer, wherein thethird protocol layer is an upper protocol layer than the second protocollayer; providing the user equipment identifier indicator and the datafrom the second protocol layer to a first protocol layer; and adding inthe first protocol layer a user equipment identifier type and a userequipment identifier to a first protocol layer data packet in responseto the user equipment identifier indicator.

[0054] According to one aspect of the present invention, the thirdprotocol layer is preferably a radio resource control (RRC) layer, thesecond protocol layer is preferably a radio link control (RLC) layer,and the first protocol layer is preferably a medium access control (MAC)layer.

[0055] According to another aspect of the present invention, the firstprotocol layer data packet is an MAC service data unit (SDU). Inaddition, a MAC protocol data unit (PDU) comprises the MAC SDU and theuser equipment identifier.

[0056] According to another aspect of the present invention, the userequipment identifier indicator is associated with at least one of cellradio network temporary identity (C-RNTI) and UTRAN radio networktemporary identity (U-RNTI). The MAC layer receives the MAC SDU and theuser equipment identifier indicator indicating a user equipment typeassociated with a radio network temporary identity (RNTI), and settingthe user equipment identifier type and the user equipment identifier aspart of MAC PDU.

[0057] According to another aspect of the present invention, the userequipment type is used in determining radio resource settings of a radiobearer, and the user equipment identifier indicator is transmitted fromthe second protocol layer to the first protocol layer. Preferably, theuser equipment identifier indicator is dynamically updated by controlinformation of the third protocol layer when the user equipment typeused in a radio communication network has changed.

[0058] According to another embodiment of the present invention, a radiocommunication system for identifying user equipment in a radiocommunication network comprises a plurality of protocol layers; meansfor providing data and a message type indicator from a RRC (radioresources control) layer to an RLC (radio link control) layer, whereinthe message type indicator is associated with a user equipmentidentifier indicator; means for setting in the RLC layer the userequipment identifier indicator in response to the received message typeindicator; means for providing the user equipment identifier indicatorand the data to a MAC (medium access control) layer; and means foradding in the MAC layer a user equipment identifier type and a userequipment identifier to a header of a MAC SDU (medium access controlservice data unit) in response to the user equipment identifierindicator.

[0059] According to another embodiment of the present invention a radiocommunication system for identifying user equipment in a radiocommunication network comprises a plurality of protocol layers; meansfor providing data and a parameter associated with a user equipmentidentifier type indicator from a third protocol layer to a secondprotocol layer, wherein the third protocol layer is an upper protocollayer than the second protocol layer; providing the user equipmentidentifier indicator and the data from the second protocol layer to afirst protocol layer; and adding in the first protocol layer a userequipment identifier type and a user equipment identifier to a firstprotocol layer data packet in response to the user equipment identifierindicator.

[0060] The foregoing and other objects, features, aspects and advantagesof the present invention will become more apparent from the followingdetailed description of the present invention when taken in conjunctionwith the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0061] The accompanying drawings, which are included to provide afurther understanding of the invention and are incorporated in andconstitute a part of this specification, illustrate embodiments of theinvention and together with the description serve to explain theprinciples of the invention.

[0062] In the drawings:

[0063]FIG. 1 illustrates a UTRAN (Universal Mobile TelecommunicationsNetwork Terrestrial Radio Access Network) structure according to a 3GPP(Third Generation Partnership Project) radio access networkspecification as applied to the conventional art and the presentinvention;

[0064]FIG. 2 illustrates a structure of a general radio interfaceprotocol according to a radio access network specification provided bythe 3GPP;

[0065]FIG. 3 illustrates an example of a protocol layer structured byradio access network construction elements;

[0066]FIG. 4 illustrates a structure of an RLC (Radio Link Control)layer and a MAC (Medium Access Control) layer in the UTRAN side;

[0067]FIG. 5 illustrates a MAC PDU (Medium Access Control Protocol DataUnit);

[0068]FIG. 6 is a flow chart illustrating a static setting of a userequipment identifier indicator in accordance with the present invention;and

[0069]FIG. 7 is a flow chart illustrating a dynamic setting of a userequipment identifier indicator in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0070] Reference will now be made in detail to the preferred embodimentsof the present invention, examples of which are illustrated in theaccompanying drawings. Hereinafter, a method for setting a userequipment identifier in accordance with the present invention will bedescribed.

[0071] Initially, the use of each user equipment identifier (forexample, C-RNTI, U-RNTI) will be described. First, in a radiocommunication network, a C-RNTI (Cell Radio Network Temporary Identity)is used when the data of a DTCH (Dedicated Traffic Channel) or a DCCH(Dedicated Control Channel) as a dedicated logical channel istransmitted to a common transport channel and when a DSCH (DownlinkShared Channel) is used as a common transport channel.

[0072] Second, a U-RNTI (UTRAN Radio Network Temporary Identity) is usedwhen the data of a DCCH (Dedicated Control Channel) is transmitted tothe common transport channel.

[0073] Accordingly, a user equipment identifier can be changed accordingto the type of the logical channel used. The user equipment identifieris preferably set in a MAC (Medium Access Control) layer. However, sincethe MAC layer cannot recognize what type of identifier is being used, ithas to receive an identifier value from an RLC layer, wherein the RLClayer is an upper layer. To further illustrate, the RLC layer has totransmit a parameter indicating the type of a user equipment identifier(for example, “0” indicating the C-RNTI or “1” indicating the U-RNTI)with an RLC PDU (Radio Link Control Protocol Data Unit).

[0074] As depicted in FIG. 5, when the parameter is referred to as auser equipment identifier indicator, a user equipment identifier typefield in the MAC layer and a pertinent user equipment identifierindicated by a user equipment identifier indicator are added to a headerof the MAC PDU which includes the RLC PDU transmitted from the RLClayer.

[0075] However, because the RLC layer entity cannot recognize the typeof user equipment identifier being used, a user equipment identifier ispreferably set by using the following two methods.

[0076] 1. Static setting method—Determining the type of a user equipmentidentifier in setting a radio bearer.

[0077] In general, when a radio bearer is set, one or two logicalchannel is used in a certain RLC layer entity. That is, in most cases,one DCH(either DCCH or DTCH) is used for one RLC layer entity. In othercases, one DCCH can be added to transmit control information requiredfor a DTCH transfer.

[0078] Accordingly, because a logical channel type is determined bysetting a radio bearer, the type (U-RNTI or C-RNTI) of a user equipmentidentifier is also determined when setting a radio bearer. Once set, theuser equipment identifier type is continually used until the setting ofthe radio bearer is changed.

[0079] In other words, an RLC layer indicates the same user equipmentidentifier to the MAC layer. When a need to change the type of the userequipment identifier arises, the setting of the radio bearer is changed,and accordingly a different type of user equipment identifier may beused.

[0080] 2. Dynamic setting method—Determining the type of a userequipment identifier according to the type of transmitted message.

[0081] The static setting method described above may be simple toimplement. However, the same type of a user equipment identifier is usedwith a certain radio bearer. For example, when a radio bearer is set touse U-RNTI (required 32 bits) for a case permitting using C-RNTI(required 16 bits), resource waste might arise in comparison with theuse of C-RNTI.

[0082] Accordingly, with the preferred embodiment of the presentinvention, a method for distinguishing a case using U-RNTI informationand a case using C-RNTI information and indicating the type of a userequipment identifier to be used in a MAC layer in transmission ofpertinent information and for informing it to an RLC layer will be used.

[0083] As described above, since only C-RNTI is used when DTCH is usedas a logical channel, the dynamic user equipment identification methodaccording to the preferred embodiment of the present invention will bedescribed in connection with the DCCH.

[0084] In general, the DCCH is a logical channel for transmittingcontrol information transmitted from a RRC (radio resources control)layer. An RRC message includes information related to call setting,maintaining and releasing functions.

[0085] The RRC layer performs a function for supporting a callconnection to prevent disconnecting during a user equipment transferfrom one cell (or node) to another cell (or another node). In somecases, a C-RNTI value may vary. In that case, it is proper to use aU-RNTI as user equipment identifier information. However, in most cases,it is possible to identify a user equipment with a C-RNTI, andaccordingly resource waste can be minimized by selectively choosing aparticular type of a user equipment identifier.

[0086] In addition, only the RRC layer recognizes what user equipmentidentifier type (C-RNIT or U-RNTI) is required when during thetransmission of a RRC message, and the RRC layer has to transmit arelated parameter to the RLC layer.

[0087] The parameter is preferably called “message type indicator”. Forexample, in the RRC layer, a message to be transmitted requires aU-RNTI. First, the RRC layer transmits an RLC SDU with a message typeindicator indicating a U-RNTI. Then the RLC layer sets a user equipmentidentifier according to the message and transmits the set indicator withan RLC PDU to the MAC layer.

[0088] Alternatively, assuming a message to be transmitted in the RRClayer requires a C-RNTI, the RRC layer transmits an RLC SDU having amessage type indicator indicting a C-RNTI. The RLC layer sets a userequipment identifier according to the message and transmits the setindicator with a MAC SDU (substantially the same as RLC PDU) to the MAClayer.

[0089]FIG. 7 is a flow chart illustrating a static setting of the typeof a user equipment identifier based on an embodiment of the presentinvention.

[0090] In setting a radio bearer, the RLC layer sets a user equipmentidentifier to be used, then transmits the set indicator to the MAC layerwith a MAC SDU, and accordingly a user equipment identifier type fieldand a user equipment identifier field are set as shown in steps 71˜73.

[0091] When the need arises, the user equipment identifier type isaltered by changing the radio bearer setting as shown in steps 73 and71.

[0092]FIG. 6 is a flow chart illustrating a dynamic setting of the typeof a user equipment identifier based on the preferred embodiment of thepresent invention.

[0093] It describes a dynamic determining method of the type of userequipment identifier in a Radio Access Network.

[0094] The RLC layer receives an RLC SDU and a message type indicatorfrom the RRC layer as shown in step 61.

[0095] Afterwards, the RLC layer checks the message type indicator,judges which one (between a U-RNTI and a C-RNTI) is to be used in thetransmission of a pertinent MAC SDU, sets a user equipment identifierindicator and transmits it to the MAC layer with the MAC SDU as shown insteps 62˜65.

[0096] In the meantime, in steps 62˜64, the RLC layer segments andreassembles the RLC SDU. The messages (usually not less than two) caneither construct one RLD PDU, or several RLC PDUs can construct onemessage. In particular, when a plurality of messages form one RLC PDU,the type of user equipment identifier indicator used for each messagecan be different (for example, a first message may be associated withU-RNTI and a second message may be associated with C-RNTI). In thatcase, a user equipment identifier indicator is set to construct a headerof a MAC PDU by using only a U-RNTI (32 bit) as a broader conceptualidentifier.

[0097] In addition, when data of at least two types of RLC SDUs areincluded in one RLC PDU and the same type of user equipment identifierindicator is used for the SDUs, the same user equipment identifierindicator is transmitted to the MAC layer with the MAC SDU(substantiallysame as the RLC PDU).

[0098] Preferably, a message type indicator and a user equipmentidentifier indicator refers to the same thing. However, becausesegmenting and reassembling of an RLC SDU are performed on the RLClayer, a user equipment identifier indicator of the RLC PDU is set basedon the message type indicator.

[0099] As described above, in the preferred embodiment of the presentinvention, data (RLC SDU) and a message type indicator as user equipmentidentification information are transmitted from the RRC layer to the RLClayer. Then the RLC layer sets a user equipment identifier indicatoraccording to the transmitted message type indicator and transmits it tothe MAC layer with the data, and appropriate user equipmentidentification information is added in the MAC layer.

[0100] Furthermore, when data transmitted or received through adedicated logical channel is transmitted through a common transportchannel and it is required to distinguish a user equipment by using auser equipment identifier, radio resource waste can be minimized by notsetting one kind of user equipment identifier in a lump but setting anappropriate user equipment identifier as occasion demands.

[0101] The preferred embodiments may be implemented as a method,apparatus or article of manufacture using standard programming and/orengineering techniques to produce software, firmware, hardware, or anycombination thereof. The term “article of manufacture” as used hereinrefers to code or logic implemented in hardware logic (e.g., anintegrated circuit chip, Field Programmable Gate Array (FPGA),Application Specific Integrated Circuit (ASIC), etc.) or a computerreadable medium (e.g., magnetic storage medium (e.g., hard disk drives,floppy disks, tape, etc.), optical storage (CD-ROMs, optical disks,etc.), volatile and non-volatile memory devices (e.g., EEPROMs, ROMs,PROMs, RAMs, DRAMs, SRAMs, firmware, programmable logic, etc.). Code inthe computer readable medium is accessed and executed by a processor.The code in which preferred embodiments are implemented may further beaccessible through a transmission media or from a file server over anetwork. In such cases, the article of manufacture in which the code isimplemented may comprise a transmission media, such as a networktransmission line, wireless transmission media, signals propagatingthrough space, radio waves, infrared signals, etc. Of course, thoseskilled in the art will recognize that many modifications may be made tothis configuration without departing from the scope of the presentinvention, and that the article of manufacture may comprise anyinformation bearing medium known in the art.

[0102] As the present invention may be manifested in several formswithout departing from the spirit or essential characteristics thereof,it should also be understood that the above-described embodiments arenot limited by any of the details of the foregoing description, unlessotherwise specified. On the other hand, it should be construed broadlywithin its spirit and scope as defined in the appended claims, andtherefore all changes and modifications that fall within the metes andbounds of the claims, or equivalence of such metes and bounds aretherefore intended to be embraced by the appended claims.

What is claimed is:
 1. A method for setting a user equipment identifierin a radio communication system having a plurality of protocol layers,the steps comprising: providing data and a message type indicator from aradio resources control (RRC) layer to a radio link control (RLC) layer,wherein the message type indicator is associated with a user equipmentidentifier indicator; setting in the RLC layer the user equipmentidentifier indicator in response to the received message type indicator;providing the user equipment identifier indicator and the data to amedium access control (MAC) layer; and adding in the MAC layer a userequipment identifier type and a user equipment identifier to a header ofa data unit of the MAC layer in response to the user equipmentidentifier indicator.
 2. The method of claim 1, wherein the data unit ofthe MAC layer comprises the MAC SDU with the user equipment identifiertype and the user equipment identifier.
 3. The method of claim 1,wherein the RLC layer receives the data and the message type indicatorassociated with the user equipment identifier indicator from the RRClayer and sets the user equipment identifier indicator fordistinguishing a user equipment appropriate to a network region tomanage the user equipment in the radio communication system.
 4. Themethod of claim 1, wherein the MAC layer receives the MAC SDU and theuser equipment identifier indicator indicating a user equipment typeassociated with a radio network temporary identify (RNTI), and settingthe user equipment identifier type and the user equipment identifier aspart of MAC PDU.
 5. The method of claim 3, wherein the MAC layerreceives the MAC SDU and the user equipment identifier indicatorindicating a user equipment type associated with a radio networktemporary identify (RNTI), and setting the user equipment identifiertype and the user equipment identifier as part of MAC PDU header.
 6. Themethod of claim 1, wherein the user equipment type is used indetermining radio resource settings of a radio bearer, and the userequipment identifier indicator is transmitted from the RLC layer to theMAC layer.
 7. The method of claim 6, wherein the user equipmentidentifier indicator is dynamically updated by control information ofthe RRC layer when the user equipment type has changed.
 8. The method ofclaim 1, wherein the user equipment type is altered according to thedata (RLC SDU) transmitted from the RRC layer to the RLC layer.
 9. Themethod of claim 8, wherein a user equipment is distinguished by usingthe user equipment identifier when the RLC PDU constructed in the MAClayer includes a RRC message having a different user equipment type. 10.The method of claim 1, wherein a user equipment is distinguished byusing a user equipment identifier distinguishable in a cell level whenthe RLC layer receives data from layers other than the RRC layer.
 11. Amethod for setting a user equipment identifier in a radio communicationsystem having a plurality of protocol layers, the steps comprising:providing data and a parameter associated with a user equipmentidentifier type indicator from a third protocol layer to a secondprotocol layer, wherein the third protocol layer is an upper protocollayer than the second protocol layer; providing the user equipmentidentifier indicator and the data from the second protocol layer to afirst protocol layer; and adding in the first protocol layer a userequipment identifier type and a user equipment identifier to a firstprotocol layer data packet in response to the user equipment.identifierindicator.
 12. The method of claim 11, wherein the third protocol layeris a radio resource control (RRC) layer.
 13. The method of claim 11,wherein the second protocol layer is a radio link control (RLC) layer.14. The method of claim 11, wherein the first protocol layer is a mediumaccess control (MAC) layer.
 15. The method of claim 14, wherein thefirst protocol layer data packet is an MAC service data unit (SDU). 16.The method of claim 15, wherein an MAC protocol data unit (PDU)comprises the MAC SDU and the user equipment identifier.
 17. The methodof claim 11, wherein the user equipment identifier indicator isassociated with at least one of cell radio network temporary identity(C-RNTI) and UTRAN radio network temporary identity (U-RNTI).
 18. Themethod of claim 16, wherein the MAC layer receives the MAC SDU and theuser equipment identifier indicator indicating a user equipment typeassociated with a radio network temporary identify (RNTI), and settingthe user equipment identifier type and the user equipment identifier aspart of MAC PDU.
 19. The method of claim 11, wherein the user equipmenttype is used in determining radio resource settings of a radio bearer,and the user equipment identifier indicator is transmitted from thesecond protocol layer to the first protocol layer.
 20. The method ofclaim 11, wherein the user equipment identifier indicator is dynamicallyupdated by control information of the third protocol layer when the userequipment type used in a radio communication network has changed.
 21. Aradio communication system for identifying user equipment in a radiocommunication network, the system comprising: a plurality of protocollayers; means for providing data and a message type indicator from a RRC(radio resources control) layer to an RLC (radio link control) layer,wherein the message type indicator is associated with a user equipmentidentifier indicator; means for setting in the RLC layer the userequipment identifier indicator in response to the received message typeindicator; means for providing the user equipment identifier indicatorand the data to a MAC (medium access control) layer; and means foradding in the MAC layer a user equipment identifier type and a userequipment identifier to a header of a data unit of the MAC layer inresponse to the user equipment identifier indicator.
 22. The system ofclaim 21, wherein the data unit of the MAC layer comprises the MAC SDUwith the user equipment identifier type and the user equipmentidentifier.
 23. The system of claim 21, wherein the RLC layer receivesthe data and the message type indicator associated with the userequipment identifier indicator from the RRC layer and sets the userequipment identifier indicator for distinguishing a user equipmentappropriate to a network region to properly manage the user equipment inthe radio communication system.
 24. The system of claim 21, wherein theMAC layer receives the MAC SDU and the user equipment identifierindicator indicating a user equipment type associated with a radionetwork temporary identify (RNTI), and setting the user equipmentidentifier type and the user equipment identifier as part of MAC PDU.25. The system of claim 23, wherein the MAC layer receives the MAC SDUand the user equipment identifier indicator indicating a user equipmenttype associated with a radio network temporary identify (RNTI), andsetting the user equipment identifier type and the user equipmentidentifier as part of MAC PDU header.
 26. A radio communication systemfor identifying user equipment in a radio communication network, thesystem comprising: a plurality of protocol layers; means for providingdata and a parameter associated with a user equipment identifier typeindicator from a third protocol layer to a second protocol layer,wherein the third protocol layer is an upper protocol layer than thesecond protocol layer; providing the user equipment identifier indicatorand the data from the second protocol layer to a first protocol layer;and adding in the first protocol layer a user equipment identifier typeand a user equipment identifier to a first protocol layer data packet inresponse to the user equipment identifier indicator.
 27. The system ofclaim 26, wherein the third protocol layer is a radio resource control(RRC) layer, the second protocol layer is a radio link control (RLC)layer, and the first protocol layer is a medium access control (MAC)layer.
 28. The system of claim 27, wherein the first protocol layer datapacket is an MAC service data unit (SDU).
 29. The system of claim 28,wherein an MAC protocol data unit (PDU) comprises the MAC SDU and theuser equipment identifier.
 30. The system of claim 26, wherein the userequipment identifier indicator is associated with at least one of cellradio network temporary identity (C-RNTI) and UTRAN radio networktemporary identity (U-RNTI).
 31. The system of claim 28, wherein the MAClayer receives the MAC SDU and the user equipment identifier indicatorindicating a user equipment type associated with a radio networktemporary identify (RNTI), and setting the user equipment identifiertype and the user equipment identifier as part of MAC PDU.
 32. Thesystem of claim 26, wherein the user equipment type is used indetermining radio resource settings of a radio bearer, and the userequipment identifier indicator is transmitted from the second protocollayer to the first protocol layer.
 33. The system of claim 26, whereinthe user equipment identifier indicator is dynamically updated bycontrol information of the third protocol layer when the user equipmenttype used in a radio communication network has changed.